Automated access ramps and other bridging devices bridge gaps and provide a pathway for persons or vehicles to cross.
Automatic ramps are very useful in the public and private transport industry. The ramps allow access onto and off trains and road vehicles for both enabled and disabled commuters as well as small vehicles such as bicycles and factor handling vehicles.
Known automatic ramps have several inherent problems. Firstly, in their retracted state they are bulky and require a large area to mount. Some of them-are also heavy which is undesirable in terms of speed and fuel efficiency if the retractable ramp is mounted on a transport vehicle. The aerodynamics and weight balance of vehicles can be affected by mounting a ramp structure to the vehicle. Most automated access ramps, due to their size, are economically unviable for retrofitting to existing transport systems. Retrofitting is made more difficult by the various structural constraints associated with mounting the ramps. Additionally, most devices need to be fully extended to perform the function of a ramp and can be unwieldy if the gap to be bridged is small.
WO 99/52738 describes an articulated ramp which is an earlier ramp by the inventors of the present invention. The ramp assembly described therein comprises a plurality of articulated segments forming a ramp body that extends from a retracted position located below the surface of the vehicle to an extended position where it bridges a gap between the vehicle and a second surface. The housing for the ramp body locates under the vehicle and houses the length of the ramp body in a substantially vertical position. Accordingly, the ramp body must be capable of significant curving through approximately 90° to achieve its final extended position. This articulated ramp assembly is awkward and very bulky, particularly when it is attached below the carriage floor of a train where space below the floor is limited and the aerodynamics and weight balance of the train could be affected by such a structure mounted to the carriages.
Furthermore, the articulated segments forming the ramp body of WO 99/52738 move in a scissor and clamping motion which present safety problems to the operator and the public. This scissor and clamping motion easily runs the risk of rendering the function of the ramp inoperable by the invasion of foreign objects, by accident or sabotage. This could result in disruption to transport schedules and possible physical injury.
The present bridging device addresses these drawbacks and the drawbacks with other known bridging devices.